2024/07/01 by Dong Li, Zhenxiang Hong, Zhenyong Hou +1 · 17 citations
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Astronomy #Astrophysics #Flare #Geomagnetism and Paleomagnetism Studies #Ionosphere and magnetosphere dynamics #Magnetic field #Magnetic reconnection #Microwave #Optics #Physics #Quasiperiodic function #Solar and Space Plasma Dynamics #Solar flare #Spectral line #Sunspot #Wavelength
paper · pdf · doi:10.3847/1538-4357/ad566c
published in The Astrophysical Journal 970(1), 77 (IOP Publishing)
openalex publication_date 2024/07/01 · openalex created_date 2024/07/19 · openalex updated_date 2026/07/28
Abstract We report the simultaneous observations of quasiperiodic pulsations (QPPs) in wavelengths of hard X-ray (HXR), microwave, Ly α , and ultraviolet (UV) emissions during the impulsive phase of an X6.4 flare on 2024 February 22 (SOL2024-02-22T22:08). The X6.4 flare shows three repetitive and successive pulsations in HXR and microwave wavebands, and they have an extremely large modulation depth. The onset of flare QPPs is almost simultaneous with the start of magnetic cancellation between positive and negative fields. The wavelet power spectra suggest the presence of double periods, which are centered at ∼200 and ∼95 s, respectively. The long-period QPP can also be detected in Ly α and UV wavebands at the flare area, and it could be observed in the adjacent sunspot. Our observations indicate that the flare QPPs are most likely triggered by accelerated electrons that are associated with periodic magnetic reconnections. The long period at ∼200 s is probably modulated by the slow magnetoacoustic wave originating from the neighboring sunspot, while the short period at ∼95 s could be regarded as its second harmonic mode.